It is common for ssb-server to have high CPU usage during gossip or indexing. Unfortunately it seems it can sometimes get stuck in that state indefinitely. Disabling legacy gossip may reduce the frequency of that occurrence. Running ssb-server in a loop with ulimit used to limit CPU time [%MmP1Rib...] might also help.

You could also get a 7inch HDMI display for $50 online (or if you have a VGA display, get a HDMI-VGA adapter), hook it up to the computer with a mouse and keyboard, install patchfoo and dillo, and then you will have a ssb client terminal that people could interact with at the space.

If you don't go the docker route, here is a general overview:

• Install Raspbian (the server one, not the desktop one). Download the image, write it to a card and boot it on the device. (or try Debian Buster or something else)
• Install Nodejs, such as by using Nodesource or NVM.
• Install ssb-server. Install the latest release with npm and/or git (after installing git).
• Set up a script to ssb-server to run automatically.
• Set up a way to distribute invite codes.
• Set up GUI by installing xserver and a terminal (stterm) and dwm or other window manager.